Select the bottom of the list..."More than one state" and move on..
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IF the amount is fairly large, you "might" be able to break out the $$ that came from your own state's bonds, but you have to calculate the exact amount yourself from the Broker's ,or Mutual fund's supplemental information sheets that they provide (somewhere,...sometimes online).
Example: you live in NC, and you have $100 in tax-exempt $$ in box 10 of a 1099-DIV form. The Mutual Fund's information tells you that 2% comes from NC bonds. So that's $2. So if you break out the $2 of NC tax-exempt interest from the $98 for all the other states, that will save you ~5% of $2 or 10 cents in state taxes ...except that with rounding to the nearest $1 that would give you a zero savings. The same situation with $1000 in box 10 would save you $1 in NC taxes.
So..is it worth the effort or not for your situation..I can't tell you that. Selecting "More than one state" is always allowed...and avoids all the extra work. Certainly you should investigate the situation with your funds (or bonds, box 8 on a 1099-INT)......But you need to know what bond funds you hold, and what the state distribution is before you can do anything beyond "More than one state".
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
